OPS 1264 (DMSP 4A F4)

OPS 1264 (DMSP 4A F4) is an active satellite operated by SAMSO (United States), launched on 1967-10-11 from Vandenberg Space Force Base, United States on the DAPP 4417 launch. After more than 59 years in orbit, it is one of the longest-surviving objects in the space catalogue. It orbits in Low Earth Orbit (LEO) at altitudes between 617 km and 750 km with an inclination of 99.2°. It travels at approximately 27,061 km/h (7.52 km/s), completing one full orbit every 98 minutes — that’s roughly 14.63 orbits per day. Its near-polar, sun-synchronous orbit means it passes over any given point on Earth at approximately the same local solar time, ideal for consistent Earth observation lighting conditions. At its current altitude, the estimated orbital lifetime before atmospheric re-entry is ~10–25 years. Orbital Radar tracks OPS 1264 (DMSP 4A F4) in real time using the latest two-line element set (TLE) data, providing live position, altitude, speed and orbital path updated continuously.

OPS 1264 (DMSP 4A F4) orbits at an average altitude of 684 km in a sun-synchronous orbit (SSO), a specialised subset of LEO where the orbital plane precesses to maintain a constant angle relative to the Sun. This provides consistent lighting conditions on every pass — essential for Earth observation, weather monitoring and environmental science. Within ±50 km of OPS 1264 (DMSP 4A F4)’s average altitude, there are currently 331 active payloads and 1,398 tracked debris or rocket body fragments — notable neighbours include TERRA, AQUA, ONEWEB-0179. With an inclination of 99.2°, OPS 1264 (DMSP 4A F4) passes over latitudes between 99.2°N and 99.2°S, providing near-global coverage including the polar regions. Polar and near-polar orbits are used for reconnaissance, weather monitoring and Earth-observation missions that need to image every part of the planet. United States operates approximately 13,279 active satellites in total, of which 86 share a similar altitude band with OPS 1264 (DMSP 4A F4).